Propulsion generator and method

A propulsion generator for use in a downhole tool to urge movement of a string of pipe within a well bore, said string of pipe comprising a bottom end portion, comprising:

• an outer tubular housing mountable to said bottom end portion of said string of pipe, said outer tubular defining a fluid flow path through said outer tubular housing to permit fluid flow through said downhole tool;
• at least one fly wheel positioned within said outer tubular housing, said at least one fly wheel comprising a center of mass;
• a plurality of fins operatively connected to said at least one fly wheel and positioned within said fluid path to receive energy from fluid flow through said flow path whereby said at least one fly wheel is rotated, said plurality of fins being rotatable as said at least one fly wheel rotates;
• and
• a mounting for said at least one fly wheel which constrains a center of rotation of said at least one fly wheel, whereby said center of mass of said at least one fly wheel is offset from the center of rotation, which results in vibrations being created during rotation of said at least one fly wheel.